Spots 
Every new session starts the same way: you paste your code review checklist again, re-explain your team’s API conventions again, walk the agent through the release process again. Forget once, and Claude Code falls back to generic habits.
A Skill ends the repetition. It’s a folder with one SKILL.md file that teaches Claude Code a repeatable task or a piece of standing knowledge. Claude reads the description and pulls the skill in automatically whenever it’s relevant, no manual invocation needed. This guide builds one from scratch in about 5 minutes. Create a personal skill that works across every project on your machine:
Then create ~/.claude/skills/api-conventions/SKILL.md with a frontmatter block and instructions (see Step 2 below). Claude Code picks it up on its next session start — no restart command needed. Total time: about 5 minutes. ⚡ Copy This Prompt: Let Claude Code Build the Skill For You
Skip Steps 1-4 below entirely and hand the whole thing to the agent instead — Claude Code can create the folder, write the SKILL.md, and validate it in one session:
The agent writes the file, then re-checks it exists and parses cleanly before telling you it’s done — instead of you writing the frontmatter by hand. Prefer to do it by hand instead of delegating to the agent? Here’s the manual version of the same steps.
Personal skills live in ~/.claude/skills/ and apply to every project you open. Project skills live in .claude/skills/ at your repo root and are loaded for anyone working in that repo (and its subdirectories, all the way down). Use project scope for team conventions, personal scope for your own habits. Each skill gets its own folder containing exactly one SKILL.md:
The opening --- must be the very first line of the file for the frontmatter to parse. description is what Claude matches against your requests, so write it the way you’d naturally ask for the task:
Optional frontmatter fields: disable-model-invocation: true makes it callable only via /api-conventions, never triggered automatically; allowed-tools restricts which tools Claude can use while the skill is active.
Start (or restart) a Claude Code session in the project, then ask a question that matches the description naturally — Claude should pull the skill in on its own. To force it regardless of description matching, call it directly: A Skill loads itself when the task matches, so you stop repeating the same instructions. Confirm the file exists and the frontmatter parses cleanly: $ ls .claude/skills/*/SKILL.md .claude/skills/api-conventions/SKILL.md $ claude plugin validate .claude/skills ✔ api-conventions: valid Run the same two commands yourself:
Inside a Claude Code session, ask “What skills are available?” — your skill should appear in the list. If the frontmatter has a YAML syntax error, the skill still loads but with no description to match against, so it’ll only work via manual /name invocation. Opening --- isn’t on line 1. Any blank line or comment before it means the frontmatter won’t parse at all.
Every new session starts the same way: you paste your code review checklist again, re-explain your team’s API conventions again, walk the agent through the release process again.